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21.
At present, apart from visual evoked potential testing, clinical neurophysiological testing is rarely used in multiple sclerosis (MS) patients at all. In MS patients with lower urinary tract, bowel and/or sexual dysfunction, which are highly prevalent in MS, clinical neurophysiological tests of the sacral nervous system have been introduced in the past and reported as abnormal. Their usefulness is – in selected patients – to substantiate the suspicion of the neurogenic nature of the pelvic organ dysfunction, but there is no specific recommendation for MS patients. Concentric needle EMG of the perineal muscles, bulbocavernosus reflex latency measurement and pudendal SEP may be particularly useful in those rare patients in whom MS may affect the conus medullaris, to demonstrate “directly” this lesion of the lower sacral segments. Clinical neurophysiological testing retains the potential to further clarify interesting research questions of correlation of nervous system function and pelvic organ dysfunction, particularly relevant for application of sophisticated new rehabilitative methods including electrical stimulation of the nervous system.  相似文献   
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BackgroundThis study aimed to investigate the relationship between lipopolysaccharide (LPS) and zonulin levels and also to show the effect of acute hyperglycemic stress induced by oral glucose tolerance testing (OGTT) on zonulin levels in pre-diabetic patients.MethodsFour groups were constituted according to the criteria of the American Diabetes Association (ADA), based on OGTT results: control group (n:40); prediabetic group (n:56), divided into two subgroups: impaired fasting glucose group (IFG) (n:36), and impaired glucose tolerance (IGT) + IFG group (n:20) and type-2 diabetes mellitus (T2DM) group (n:45).ResultsZonulin and LPS did not significantly differ between the prediabetes and control groups, but were significantly higher in the T2DM group compared to both the prediabetic and the control group (P < 0.001). After OGTT, zonulin and LPS were significantly higher in the prediabetes group compared to the control group (P < 0.01 and P < 0.05, respectively), and significantly lower in the IFG and IFG + IGT groups compared to the T2DM group (P < 0.001, P < 0.001 and P < 0.001, P < 0.001, respectively). A positive correlation was detected between fasting zonulin and 2-hour zonulin (r = 0.727, P < 0.001) and between fasting LPS (r = 0.555, P < 0.001) and 2-hour LPS (r = 0.567, P < 0.001) in the prediabetic group. Increased zonulin and LPS levels and the positive correlation between these levels during the prediabetic period although non significant suggests onset of intestinal permeability.ConclusionsDuring acute hyperglycemia in prediabetic patients, up-regulation of zonulin and LPS may affect intestinal function. The intestines may play a key role in up-regulation of glucose and the pathogenesis of diabetes.  相似文献   
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Background

Liver steatosis is associated with poor outcome after liver transplantation and liver resection. There is a need for an accurate and reliable intraoperative tool to identify and quantify steatosis. This study aimed to investigate whether surface diffuse reflectance spectroscopy (DRS) measurements could detect liver steatosis on humans during liver surgery.

Methods

The DRS instrumentation setup consists of a computer, a high-power tungsten halogen light source and two spectrometers, connected through a trifurcated optical fiber to a hand-held probe. Patients scheduled for open resection for liver tumors were considered for inclusion. Multiple DRS measurements were performed on the liver surface after mobilization.

Results

In total, 1210 DRS spectra originated from 38 patients, were analyzed. When applying the data to an analytical model the volumetric absorption ratio factor of fat and water specified an explicit distinction between mild to moderate, and moderate to severe steatosis (p < 0.001). There were significant differences between none-to-mild and moderate-to-severe steatosis grade for the following parameters: reduced scattering coefficient (p < 0.001), Mie to total scattering fraction (p < 0.001), Mie slope (p = 0.003), lipid/(lipid + water) (p < 0.001), blood volume (p = 0.044) and bile volume (p < 0.001).

Conclusion

This study shows that it is possible to evaluate steatosis grades with hepatic surface diffuse reflectance spectroscopy measurements.  相似文献   
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Central Illustration. Pathophysiological pathways providing a causal link between high plasma concentrations of lipoprotein(a) (Lp(a)) and atherosclerotic vascular disease and aortic valve stenosis (AVS). Clinical outcomes are related to accelerated atherosclerosis complicated by atherothrombosis (myocardial infarction, stroke), peripheral artery disease (PAD) or aortic valve replacement (AVR) caused by valve calcification and aortic stenosis. Apo(a): apolipoprotein(a); LDL: low-density lipoprotein; OxPL: oxidized phospholipids; NSFA: Nouvelle Société Francophone d’Athérosclérose; SP: serine-protease domain; V: plasminogen kringle V (reproduced with permission).
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Background

In microarray data, wide-scale correlations are numerous and increase the number of genes correlated to a test condition (phenotype, mutation status, etc.) either positively or negatively. Several methods have been developed to limit the effect of such correlations on the false discovery rate, but these may reject too many genes that have a mild or indirect impact on the studied condition. We propose here a simple methodology to correct this spurious effect without eliminating weak but true correlations.

Results

This methodology was applied to a microarray dataset designed to distinguish heterozygous BRCA1 mutation carriers from non-carriers. As our samples were collected at different times in the morning, we evaluated the effect of correlations due to circadian rhythm. The circadian system is a well-known correlation network, regulated by a small number of period genes whose expression varies throughout the day in predictable ways. The downstream effects of this variation on the expression of other genes, however, are incompletely characterized. We used two different strategies to correct this correlation bias, by either dividing or multiplying the expression of correlated genes by the expression of the considered period gene according to the sign of the correlation between the period gene and correlated gene (respectively positive or negative).

Conclusions

We observed a linear relationship between the number of false-positive/negative genes and the strength of the correlation of the candidate gene to the test condition. BRCA1 was highly correlated to the period gene Per1; our correction methodology enabled us to recover genes coding for BRCA1-interacting proteins which were not selected in the initial direct analysis. This methodology may be valuable for other studies and can be applied very easily in case of well-known correlation networks.  相似文献   
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